A large and growing number of households have pets. Studies have shown that pet owners often treat their pets as they treat close friends and relatives. Owners include pets in holiday celebrations, and often refer to themselves as parents of their pets. Such affinity is tangibly demonstrated in the rapid growth of a multibillion dollar pet industry with an increasing demand for pet products that mimic human products.
Health conscious consumers are also demanding higher quality pet food that is not only closer in ingredient quality to human food, but also looks less processed and more natural. However, conventional pet food producers seldom focus on the visual impact of pet food that heightens aesthetic appeal to a purchaser, even if they integrate advanced ingredients more commonly found in food produced for human consumption. Since a traditional manufacturing goal is reproducibility and uniformity, industrial cutting machines used in these conventional pet food processes are primarily designed to deliver products with consistency in shape, texture and size. Therefore, pet food packages typically contain edible pieces, or kibbles, where each kibble is generally of uniform shape and size, often readily appearing glazed or processed. For example, pet jerky treats are made by extrusion through generally uniform die openings, producing strips or rods that are typically uniform in shape, and which are then typically cut in uniform pieces that are rectangular (flat) or cylindrical (rod) in appearance. Pet food resembling red meat marbled with fat has been made by extruding or pressure casting a blend of red meat and white fat, but the end product is again a plurality of food pieces of generally uniform shape and size.
Manufacturing techniques used to produce human food are often not cost effective for pet foods. For example, jerky-style products for human consumption are made from sliced premium muscle meat, and contain almost no grains, starch or carbohydrates. Because of the high concentration of muscle meat and fat, increased time is required for processing of human grade jerky, especially drying. The increased use of meat, lack of carbohydrates, and the slower drying process results in a final product that shrinks and forms into long strips of randomly wrinkled meat, in the distinct rugged appearance of natural jerky with which consumers are familiar, and often associate with higher quality.
While human grade jerky may certainly be used as pet food, it would be cost prohibitive for most pet owners. This is because human grade jerky is primarily marinated meat, often costly premium meat. When the product is almost 100% meat, it also becomes difficult to process efficiently in high volumes, thereby increasing processing time and costs. To reduce ingredient costs, pet jerky treats use lower amounts of meat (typically 20-40%), and usually do not use any premium muscle meat. To compensate for lower amounts of meat in pet jerky, 20-40% of flour or starches must be added, along with other ingredients such as vegetables, preservatives, and flavor enhancers. Besides lowering ingredient costs, the flour and starch significantly improve processing ability for high volume manufacturing, further reducing production times and costs.
Human grade jerky is usually designed for relatively short shelf lives. Pet food, on the other hand, is engineered to be stored (if necessary) for eighteen months after manufacturing before it is consumed, and therefore requires a substantially longer shelf life. Human grade jerky packets, once opened, become stale in less than a week. Pet jerky, however, is expected to last for up to three months after the package is opened. The delay in the storage and consumption of pet foods requires more careful ingredient selection, preservation of freshness with antioxidants, processing that avoids insects and rancidity, careful packaging and storage. This kind of food processing, with a higher mix of inexpensive ingredients, particularly carbohydrates, lends itself well to traditional extrusion techniques.
Since high moisture meat products tend to spoil quickly, such products are usually sold in cans in the pet food market, and are more typical as cat food. Pet food or kibble with low moisture content (typically less than 10%), are dry and hard, and less palatable to pets. Semi-moist pet food, typically having moisture content between 15 and 30%, is very popular with animals since it has a texture and palatability that is closest to meat. However, as discussed, semi-moist pet food is difficult to store in a stable condition, without canning or refrigeration, for long periods.
Thus, neither conventional pet food manufacturing processes nor traditional production techniques of jerky-style products for human consumption can meet the requirements of cost-effectively manufacturing jerky products for pets of variable thicknesses, texture, and non-uniform shapes and sizes that remain semi-moist, and shelf-stable without refrigeration for long periods under normal storage conditions. Furthermore, there is no conventional food processing method for either pet or human food that can produce a continuous line of jerky pieces that mimic the natural, irregular, wrinkled and rugged look and feel of human grade jerky produced traditionally.